Duplicator



May 23, i939.

K. o. cHRlsTlANsoN DUPLICATOR 2 Sheets-Sheet 2 Filed March 10, 1938 Arroz/vens' Patented May 23, 1939 PATENT OFFICE 2,159,471 nUPrJcA'roR Kenneth O. ChrlstiansonfMankato, Minn., assignor toCreative AEducational Society, Mankato, Minn., a partnership. composed of G. R. Peterson, J. C. Mackin, A. D. Tinkler, and

K. 0. Christiansen Application March 10, 1938, Serial No. 195,080

8 Claims.

'I'his invention relates to new anduseful improvements in duplicators, and an object of the invention is to provide such a device which is exceedingly simple and convenient to operate', and the construction of which is such that each impression will be accurately placed on the sheet.

A further object is to provide a duplicator comprising a printing frame providedrwth means at one end for clampingly securing the sheets to be printed thereto in superimposed relation, and which means also vserves to square the printing member or rocker'with `the sheets supported on Y the printing frame.

'A further object is to provide a printing blanket having novel means for detachably securing it to the rocker, whereby it may readily'and conveniently be detached therefrom, when necessary, and a new one substituted therefor.

Other objects' of the invention reside in the novel construction of the printing frame, which has a channel member at one end providinga clamp for detachably securing a stack of sheets to be printed to the printing frame; in the suction means provided Yon the printing frame for ysecuring it in operative position upon a table or other at surface; in the novel construction of the hookv elements provided at the ends of the blanket for detachably securing it in position'on the rocker; and, in the simple and inexpensive construction of the apparatus, whereby it may readily be manufactured and sold to the trade at comparatively low cost.

Other objects of the invention will appear from the following description and accompanying drawings and will be pointed out in the annexed claims.

In the accompanying drawings there has been disclosed a structure designed to carry out the p various objects of the invention, but it is to be understood that the invention is not confined to the exact features shown as various changes may be made within the scope of the claims which follow.

In. the drawings:

Figure 1 is a longitudinal sectional view of my improved duplicator, showing the general construction thereof;

Figure 2 is a plan view of the apparatus;

Figure 3 is a perspective View showing one end of the rocker with one end of the blanket detached therefrom;

Figure 4 is a perspective view of the convexed or lcurved surface of the rocker, showing the manner of transferringV an impression thereon f from a master sheet; and

f Figure 5 is a longitudinal sectional view showing a rocker of slightly different construction.

The. novel duplicator herein disclosed is shown comprising a printing frame, generally indicated by the numeral 2, and comprising a plate 3, preferably having suitable rails 4 and 5 at the ends thereof, as best shown in Figure 1. Two or more suction cups 6 offconventional construction, are secured to the front rail 4 for securing the frame to a table top or other relatively smooth surface. If deemed necessary similar suc-tion cups may be provided at the opposite end of the frame 2.

The sheets to be printed are placed upon the plate 3 of the frame, preferably in the form of a stack, as shown at 1 in Figure 1. Suitable upright alining pins 8 are secured to the frame 2 at one end, against which one edge of the stack of sheets 1 may be engaged to aline or square the pack ofk sheets with the frame 2.

Means is provided for clamping or securing the pack of sheets to the frame 2, whereby they are not likely to become disarranged on the frame, when impressions are successively made on said sheets. Such means is shown comprising an elongated channel-shaped member, generally indicated by the numeral 9. `This member is shown made of sheet metal and has its upper wall curved to provide an outwardly facing concave wall whose upper edge is bent outwardly and downwardly to provide an upright abutment wall II, as best shown in Figure 1. The lower edge of the wall II is adapted to engage the uppermost sheet of the pack 1. Suitable clamping elements, which may be in the form of wing nuts I2, are received in threaded engagement with screws or studs I3 anchored to the front cross rail 4. When the wing nuts I2 are turned in one direction, the lower edge of the upright wall of the clamping member 9 will be forced into engagement with the upper sheet of the pack, thereby rmly securing the pack to the frame in proper relation with respect thereto.

Another important feature of the invention resides in the novel construction of the means for transferring the impression onto each sheet of the pack 1. Such means is shown comprising a'rocker, generally indicated by the numeral I4. This rocker has a convex wall I5 against which the usual printing blanket, generally indicated by the numeral I6, is seated. The frame of the rocker I4 comprises side walls I'I and I8 having inwardly turned flanges I9, which are suitably secured to the curved Wall I5 to provide in eect, an integral structure. The opposite ends of the curved wall l5 are bent inwardly to vides a very convenient grip for an operator,

when manipulating the rocker upon the printing frame.

Y Another feature of the invention resides in the means provided for the printing blanket I6 to the curved wall of the rockenn The body of the printing blanket I6 is Of more ori.

less standard construction, and embodies a layer of gelatin which may be secured to a suitable inelastic fabric which forms 'a backing there for. capable of receiving an impression i25 `from a master sheet 26, kas shown, 'for example, in Figure 4.

The means for detachably .securing the printing blanket to the rocker .is best illustrated vin Figure 3, and as here shown, comprises a pair of bars 21,on'e"sec-ured to each fen-d Yof .the blanket by suitable means such as small rivets 218. To prevent 'tearing -of the printing blanket i6 at the points whe-re the rivets :28 pass through, suitable bars 36 are fitted against the Iopposite slide of the blanket in alinement with the bars 2l.. These bars are apertured to receive the rivets 28, whereby the backing sheet of the blanket is securely clamped between the bars 21 yand 80. Each bar l2l is provided with spaced hook elements 29 which are substantially S-shaped in' crosssection. These hooks are adapted to be selectively ree ceived in slots 3l "or 32 provided in the horizontal flanges 2l of the rocker. Note particularly yZfiigure :1, wherein the blanket is yshown in operative position upon the rocker. Because of the unique shapes Iof the hook elements 28., they are not likely to become disengaged from the slots `3l or 32, when the printing blanket is secured to the rocker.

By reference to Figure 1, it will be noted that the bars 2 to which the hook elements 29 are secured, -are spaced inwardly from the edges 33 of the backing of the printing blanket I6. By thus inwardly spacing the hooks 29 from the opposite ends of the blanket, theSeo-Verhanging ends may readily be grasped by the operator, whereby the oper-ation of removing or mounting the printing blanket -upon thev rocker fis 'facilitated. By providing two -slots 3| and 32 in eac-h horizontal flange `2| of the rocken, the printing blanket :may be Akept under the proper tension by simply inserting the `hooks in the proper slots, as will Vreadily be understood.

.In the operation of this novel device, the lpac of sheets to receive impressions .is placed upon the plate 3 of the printing :frame 2, with :one edge engaging the pins 8. When thus' positioned, the lower edge of the upright Wall Il of the clamping member 9 ywill fbe positioned upon the uppermost sheet of the stack, whereby when the wing nuts 12 are tightened, the sheets will 'be rmly clamped in position xupon the printing fra-me :in square relation thereto.

The rocker is then operated upon the fshee'ts, as shown in Figure l, i-t being understood that a printing blanket Abea-ring the 1desired impression or character, h'as `first been secured to the rocker. In making the impression ton each sheet, the forward rend of the rocker is 'conveniently abutted The printing blanket is, as is Well-known,

sheets may be printed without removing any of against the abutment wall Il of the clamping member 9, as shown in full lines in Figure 1, whereby it is squared with respect to the sheet. It is then rocked backwardly to the position shown in dotted lines in Figure 1, and as it reaches the position shown in dotted lines, it may be lifted upwardly from the printing frame by the operator. When the rocker is thu'slifted olf the printing frame, the free or bottom end of the sheet which has just received an impression, will .be lifted olf the pack, because of its tendency to adhere to the printing surface at the point A in Figure""1; 'adherence of the printed sheet to the 'rocken'enables the operator to readily grasp the-free *end Vof the printed sheet and swing it upwardly to the dotted line position shown at B in VFigure l, after which it may drop by gravity to the dotted line position indicated at C. It will thus be seen that, if desired, the entire Pack of the sl'ieetsfrom theY frame 2.-

The apparatus has been found very practical and convenient to operate, and may be :operated .by an inexperienced persony withl perfect results.

VIn Figure 5, there is shown a rocker 34 of slightly different construction, whose body is preferably .formed of a moldedmaterial for example, such 4as Bakelite.: The rocker 34 has a suitable handle vwh'ereby it may be conveniently operated: y 1 f In the form shown in Figure 5, an inwardly turned Aflange 36 is securedto kone end o'f the rocker adapted to be engaged by a hookfelement 31, secured t'o one en-d of 'the printingl blanket 38. 'Ihe main body of this blanket is constructed ina manner similar to 'the blanket l-S shown in the previous iifgures.

A transverse Vgroove'or'recess 39 is provided in the upper surface 'of the-opposite end of the rocker 34 adapted-to receive a Vclamping member 4|,.preterablyin the form vof Aan inverted channeL-asfshown. This fcliannel member is shown provided at each end with an arm142 mounted on suitable -pivot pins or a Ashaft 43, whereby the clamping member 4l :maybe swung upwardly to an inoperative position, as shown in dotted lines in Figure 5. The ari-ns 42 also inseparably connect the clamping'member 4l to the rocker. A keeper 44 is pivotally supported upon 'a pivot screwy45, whereby it may be swung to a position over the channel member 4I to secure it in locked position, as shown in full lines in Figure 5. When the keeper 4'4 -is turned at substantially right angles tothe position shown in Figure `5, the channel member may be swung upwardly to inoperative position, Whereby the printing blanket 38 may readily be detached from the rocker.

To attach the printing blanket to the rocker 34, the end thereof vhaving the hook 31 is attached to the inclined ange 36. The blanket is then pulled tautly around the convexed or rounded surface of the. body oi the rocker and has its opposite end pulled inwardly over the groove 39 provided in the upper surface of the opposite fend of the rocker. The channel member V4I .is then swung downwardly into engagement with the end of the blanket and the keeper swung into locking position 4over the channel member 4l, -as shown. The free end portion of the blanket is preferably bent backwardly upon itself, before the clamping member issecurely locked in the groove 39. The rocker shown in Figure 5 is operated in identically the same manner as the lone shown in Figures 1 and 3.

A feature of the present invention resides in the unique construction of the printing blanket, whereby it may readily be removed from the rocker and a new one substituted therefor, when necessary. The blanket is inexpensive in 'con'f struction, and each is supplied With hook elements 29, as shown in the drawings. Thus, a supply of these blankets may be carried in stock to facilitate making different impressions which, as previously stated, is a very desirable feature.

I claim as my invention:

l. In a duplicator, a printing frame upon which the sheet to be printed is supported, means at one end of the frame for squaring the sheet thereon, and a clamping member engageable with end' of the sheet and adapted to securely clamp the sheet in position on the frame, Whereby the sheet cannot be displaced on the frame by a printing member, when the latter is operated to make an impression on the sheet, said clamping member having an upright Wall adapted to be engaged by one end of the printing member, thereby to square said member with the sheet.

2. In a duplicator, a printing frame adapte-d *ffreceive a stack of sheets to be printed, spaced pins at one end of said frame engageable with oneedge of said stack of sheets, thereby to square `the stack.v upon the frame, an elongated clamprfiange into clamping engagement with the stack of sheets to secure it to the printing frame, said flange forming an abutment wall adapted to be engaged by one end of a printing member, thereby to square said member with the stack of sheets.

3. In a duplicator, a printing frame adapted to receive a stack of sheets to be printed, spaced pins at one end of saidframe engageable with one edge of said stack of sheets, thereby to square the stack upon the frame, a substantially U-shaped lclamping member having an upright wall the lower edge of which is adapted to engage the adjacent upper surface of the'stack of sheets, and threaded elements for forcing the clamping member into clamping engagement with said stack of sheets to secure it to the print- Ving frame, the uprightv wall of said clamping another, means for securing a plurality of sheets n in position on said frame, a rocker having a con- Vex surface, a printing blanket overlying said convex surface and suitably secured thereto, and

said securing means having an upright wall for squaring the rocker With the stack of sheets each time an impression is made on one of said sheets, said sheet securing means permitting all of the sheets of the stack to be printed before the printed sheets are removed from the frame.

5. In a duplicator, a printing frame for supporting the sheets to be printed, a rocker having a printing blanket detachably secured thereto and adapted to receive an impression to be transferred onto said sheets, a plurality of transversely disposed slots at one end of the rocker, and a substantially S-.shaped hook element secured to one end of said blanket adapted to be selectively received in said slots, thereby to tension the blanket on the rocker.

6. In a duplicator, a printing frame for supporting sheets to be printed, a rocker, a printing blanket deta'chably secured to said rocker and adapted to receive an impression to be transferred onto said sheets, a plurality of transversely disposed slots in an upper wall of the rocker, spaced apart lengthwise of and S-shaped hook elements secured to the blanket and adapted to be received in said slots, thereby to detachably secure the blanket to the rocker.

'7. In a duplicator, a printing frame for supporting sheets to be printed, a rocker, a printing blanket detachably secured to said rocker and adapted to receive an impression to be transferred onto said sheets, an inwardly turned flange at ing means whereby the blanket may be properly tensioned on the rocker.

8. In a duplicator, a printing frame having means at one end for squaring the sheets to be printed, a transversely disposed clamping member of channel cross-section having one leg adapted to engage the uppermost sheet of the stack of sheets, thereby to secure the stack in position upon the frame, said clamping member having an upright wall disposed transversely of the sheets, a printing member having a curved surface adapted to be rolled over the uppermost sheet of the stack to make a printing impression thereon, said printing member having one end adapted to be engaged with the upright wall of the clamping member, whereby the printing member is squared with the sheets, and the clamping member being so constructed and related to the printing frame that as each sheet is printed, it may be folded over the clamping member without detaching it therefrom, whereby all of the sheets in the stack may be printed before any of said sheets are removed from the frame.

KENNETH O. CHRISTIANSON. 

